摘要
【目的】探讨休眠期苹果树体不同器官生物量与氮素分布的规律。【方法】以9年生红富士苹果树为对象，对休眠期不同器官及其皮层和木质部的生物量、氮含量与氮累积量进行了详细分析。【结果】休眠期苹果树体地上部与根系的生物量分别占树体的生物量的77．17％和22．83％；树体皮层和木质部生物量分别占单株树体生物量的21．29％和77．96％；根系生物量随深度增加而降低，71．18％的根分布在O～40cm土层中。树体各器官皮层的氮含量均高于其木质部；枝及其皮层和木质部氮含量随枝龄的增加而减少；同一土层细根的氮含量大于粗根。休眠期苹果树体69．85％的氮累积在地上部，且主要贮藏在3～8年枝的木质部，而根系的氮素主要贮藏于0～20cm的粗根木质部；根系氮累积量随深度增加而降低；在同一土层中，粗根氮累积量明显高于细根。【结论】苹果树休眠期氮素在树体内的储存量表现为地上部大于根系，木质部大于皮层。
[Objective] The objective of this study was to find biomass and nitrogen distribution in dif- ferent parts of dormancy apple trees. [Method] 9 year-old red ＂Fuji＂ apple trees were used as materials in the experiment. Biomass, nitrogen concentration and accumulation in organs and their cortex and xylem of dormancy apple trees were analyzed. [Result] The results show that above ground part and root system bi- omass account for 77. 17% and 22. 83%, respectively. Cortex and xylem dry weights are respectively 21.19% and 77.96% of a tree. With the depth,root system biomass reduces. And 71.18% roots distribute to 0--40 cm soil layer. Nitrogen concentration in cortex was higher than that in xylem. Nitrogen concentra- tion of branches and their cortex and xylem fall, with branch age. And nitrogen content of fine roots is higher than that of large roots in the same soil layer. 69.85 % total nitrogen in apple tress store in above ground part. And nitrogen mainly accumulates in 3-8 year branch xylem. But root system nitrogen accumulation mainly assigns to large roots xylem. Nitrogen accumulation of root system declines with soil layer. At the same soil layer, nitrogen accumulation in large roots is higher than that in fine roots. [Conclusion] Nitrogen accumulation and storage of the tree is higher in above ground and xylem than that in the roots and cortex.
出处
《西北农林科技大学学报（自然科学版）》
CSCD
北大核心
2008年第1期153-157,共5页
Journal of Northwest A&F University(Natural Science Edition)
基金
农业部“948”重大引进项目(2003-Z53)
PPI/PPIC资助项目
关键词
苹果树
休眠期
生物量
氮素分布
apple tree
dormancy
biomass
nitrogen distribution
